Selected papers on our projects.
Chilingaryan S., Mirone A., Hammersley A., Ferrero C., Helfen L., Kopmann A., Dos Santos Rolo T., Vagovic P.
in IEEE Transactions on Nuclear Science, 58 (2011) 1447-1455, 5766797. DOI:10.1109/TNS.2011.2141686
Advances in digital detector technology leads presently to rapidly increasing data rates in imaging experiments. Using fast two-dimensional detectors in computed tomography, the data acquisition can be much faster than the reconstruction if no adequate measures are taken, especially when a high photon flux at synchrotron sources is used. We have optimized the reconstruction software employed at the micro-tomography beamlines of our synchrotron facilities to use the computational power of modern graphic cards. The main paradigm of our approach is the full utilization of all system resources. We use a pipelined architecture, where the GPUs are used as compute coprocessors to reconstruct slices, while the CPUs are preparing the next ones. Special attention is devoted to minimize data transfers between the host and GPU memory and to execute memory transfers in parallel with the computations. We were able to reduce the reconstruction time by a factor 30 and process a typical data set of 20 GB in 40 seconds. The time needed for the first evaluation of the reconstructed sample is reduced significantly and quasi real-time visualization is now possible. © 2006 IEEE.
Phillips, D.G et al.
in IEEE Nuclear Science Symposium Conference Record
2010, Article number 5874002, Pages 1399-1403
This article will describe the procedures used to validate and characterize the combined hardware and software DAQ system of the KATRIN experiment. The Mk4 DAQ Electronics is the latest version in a series of field programmable gate array (FPGA)-based electronics developed at the Karlsruhe Institute of Technology’s Institute of Data Processing and Electronics (IPE). This system will serve as the primary detector readout in the KATRIN experiment. The KATRIN data acquisition software is a MacOS X application called ORCA (Object-oriented Real-time Control and Acquisition), which includes a powerful scripting language called ORCAScript. This article will also describe how ORCAScript is used in the validation and characterization tests of the Mk4 DAQ electronics system. © 2010 IEEE.
Chilingaryan, S., et al.
in Journal of Physics: Conference Series. Vol. 219. No. 4. IOP Publishing, 2010.
During operation of high energy physics experiments a big amount of slow control
data is recorded. It is necessary to examine all collected data checking the integrity and validity
of measurements. With growing maturity of AJAX technologies it becomes possible to construct
sophisticated interfaces using web technologies only.
Our solution for handling time series, generally slow control data, has a modular architecture:
backend system for data analysis and preparation, a web service interface for data access and a
fast AJAX web display. In order to provide fast interactive access the time series are aggregated
over time slices of few predefined lengths. The aggregated values are stored in the temporary
caching database and, then, are used to create generalizing data plots. These plots may include
indication of data quality and are generated within few hundreds of milliseconds even if very
high data rates are involved. The extensible export subsystem provides data in multiple formats
including CSV, Excel, ROOT, and TDMS. The search engine can be used to find periods of
time where indications of selected sensors are falling into the specified ranges. Utilization of
the caching database allows performing most of such lookups within a second. Based on this
functionality a web interface facilitating fast (Google-maps style) navigation through the data
has been implemented.
The solution is at the moment used by several slow control systems at Test Facility for
Fusion Magnets (TOSKA) and Karlsruhe Tritium Neutrino (KATRIN).